AstraZeneca's largest shareholder urges the firm to go back to the table with Pfizer despite rejecting 'final' offer

AstraZeneca's largest shareholder has called for it to re-open talks with Pfizer as soon as possible, renewing fears that Britain’s second-biggest drugs maker could be sold to the American predator.

Blackrock, which holds 7.8 per cent of Astra’s shares, is understood to have privately urged the group to re-start talks with the Viagra maker, heaping pressure on the British company’s board, which this week batted away Pfizer’s ‘final’ £55-a-share offer as too low.

Astra chief executive Pascal Soirot also told MPs the deal could delay the development of life-saving drugs.

Back to the drawing board: Blackrock's widely-reported intervention adds to the tally of shareholders criticising Astra

Deal or no deal: Unless a deal is reached by 5pm on Monday the companies must part ways for at least three months with Pfizer not allowed to approach Astra unsolicited for a full six months

But the Frenchman and his board have faced increasing calls from investors to return to the negotiating table once the legal lockdown period ends in August.

It was reported that in its discussions with management, Blackrock supported the decision to reject a £55 bid but was keen for the companies to start talking again as soon as possible. More than a sixth of shareholders have now urged Astra to try to reach a higher price.

During negotiations last weekend, the UK company said it would have considered a bid of £58.50.

But because of UK takeover rules, Pfizer was barred from raising its offer any further.

Unless a deal is reached by 5pm on Monday, which looks increasingly unlikely, the companies must part ways for at least three months – with Pfizer not allowed to approach Astra unsolicited for a full six months.

But once the first deadline passes, it is thought Astra’s board will face strong pressure to re-open talks with the US firm.

Between January and last Sunday, Pfizer had submitted four bids for AstraZeneca, climbing from £46.61 a share to last weekend’s £55 offer – the equivalent of almost £70billion. Shares, which fell sharply after the bid was rejected on Monday, slipped again yesterday, falling 145p to 4275p.

Blackrock’s widely-reported intervention, which the US fund behemoth refused to confirm last night, adds to the tally of shareholders criticising Astra.

The third largest, AXA, told the Mail this week it felt the decision to walk away was ‘not in our interests’.

Legal & General, the sixth-largest investor, was also reported to have written to the board voicing concerns over the speed of its rejection of Pfizer’s approaches.

Schroders, the 12th-biggest holder, has also publicly criticised the company.

But others have backed Astra’s board. Investor AB – which acts for the powerful Swedish Wallenberg family – has been the most vocal critic of the Pfizer bid among shareholders, urging the company not to sell at any price.